Facile and rapid preparation of magnetic octadecylamine nanocomposite and its application as a capable adsorbent in magnetic dispersive solid phase extraction of some polycyclic aromatic hydrocarbons from wastewater samples

In this research, modified magnetic nanoparticles were prepared to be served as a magnetic dispersive solid phase extraction adsorbent for the simultaneous extraction and preconcentration of some polycyclic aromatic hydrocarbons from different wastewater samples. This method was followed by a dispersive liquid-liquid microextraction procedure to achieve high sensitivity and enrichment factors. Ultimately, the analytes were analyzed by gas chromatography-flame ionization detection. The adsorbent was the octadecylamine co-precipitated by Fe3O4 which exhibited high adsorption capability towards the target compounds. The developed process was performed by dispersion of the octadecylamine@Fe3O4 nanoparticles into an aqueous sample solution containing the target analytes by vortexing. Then, the magnetic adsorbent was collected by applying an external magnetic field followed by adding acetonitrile to elute the analytes from the adsorbent by vortexing for a few minutes. By utilizing an external magnet once again, the adsorbent was separated and the attained eluent was mixed with an extraction solvent at mu L-level and speedily injected into deionized water. After centrifugation, an aliquot of the sedimented phase was injected into the separation system. The experimental parameters of both steps were investigated and optimized. Under the optimized extraction conditions, the proposed method provided low limits of detection (0.11-0.30 mu g L-1) and quantification (0.40-1.0 mu g L-1), and satisfactory precision with relative standard deviations in the ranges of 2-5% for intra- (n = 6) and 3-6% for inter-day (n = 4) precisions. Satisfactory extraction recoveries and high enrichment factors were obtained in the ranges of 63-84% and 506-676, respectively. The performance and results of this research unfold that the developed method is easy, practical, highly efficient, precise, and rewarding as the environmental perspective.